1. Field of the Invention
The present invention relates to engine control devices capable of controlling the operation of an internal combustion engine mounted on a vehicle.
2. Description of the Related Art
There have been known and used vehicles equipped with an engine control device capable of providing an idling reduction function (or an idle stop function). The engine control device has the idling reduction function which automatically stops the operation of an internal combustion engine (hereinafter, the engine) when a predetermined engine stop condition is satisfied.
A patent document 1, Japanese patent No. 5609826 discloses a conventional engine control device. This conventional engine control device detects that a vehicle stopped state, i.e. the vehicle is stationary and the engine is still operating. In this situation, the conventional engine control device executes an automatic engine stop process so as to automatically stop the engine of the vehicle operating when the predetermined engine stop condition is satisfied in the vehicle stopped state. The engine control device having the automatic engine stop function can reduce fuel consumption of the vehicle.
In order to further reduce the fuel consumption of the vehicle, the conventional engine control device executes the automatic engine stop process in a decelerating state of the vehicle (hereinafter, the decelerating state) when detecting that the speed of the vehicle is reduced and the automatic engine stop condition is satisfied.
Still further, the conventional engine control device executes the automatic engine restart process so as to automatically restart the operation of the engine of the vehicle when a predetermined engine restart condition is satisfied after the engine has been stopped by the automatic engine stop process.
However, the conventional engine control device disclosed in the patent document 1 inhibits the execution of the automatic engine stop process in the decelerating state at least until the automatic engine stop process at the first time has been executed in the vehicle stopped state. That is, the conventional engine control device detects, in the vehicle stopped state, whether the automatic engine stop process, including the automatic engine stop process to be executed in the decelerating state, can be correctly executed. The conventional engine control device further attempts to avoid unexpected malfunction due to a problem in which the automatic engine stop process is not executed in the decelerating state in which the speed of the vehicle is reduced.
When the automatic engine start process is correctly executed after the automatic engine stop process at the first time has been executed in the vehicle stopped state, the conventional engine control device allows the execution of the automatic engine stop process during the decelerating state of the vehicle. That is, the conventional engine control device detects, during the vehicle stopped state, whether or not the automatic engine restart process is correctly executed. In addition, the conventional engine control device intends to avoid an occurrence of an unexpected uncomfortable state of the vehicle due to incorrect execution of the automatic engine stop process during the decelerating state.
The conventional engine control device inhibits the execution of the automatic engine stop process in the decelerating state, i.e. inhibits the execution of the automatic engine stop process until the automatic engine stop process at the first time has been executed in the vehicle stopped state.
Accordingly, the conventional engine control device cannot execute the automatic engine stop process in the decelerating state until the automatic engine stop process at the first time has been executed in the vehicle stopped state even if there is a possible opportunity to correctly execute the automatic engine stop process in the decelerating state. This prevents further fuel consumption reduction.